1. Field of the Invention
The invention relates to a method for establishing a parametric model, and more particularly, to a method for establishing a parametric model of a semiconductor process.
2. Description of the Related Art
Lithography technology is important in semiconductor processes. Lithography technology must conform to the specifications of the new generation of circuit designs, or the semiconductor industry will be faced with a dilemma. In recent years, integrated circuit (IC) design specification has shrunk in size each year. Therefore, Lithography technology related to pattern definition effectiveness must meet the demands for the development of the exposure device, the establishment of the process, mask making and other related technologies, and the investments in manpower, material resources, financial resources and time are also important factors.
In the traditional lithography system, optical lithography equipment is standard. However, for a deep ultraviolet (DUV) light, a resolution of the DUV light is related to a wavelength of the light, thereby having limits. Therefore, lithography technology is gradually developing toward the electron beam, X-ray, extreme ultraviolet (EUV), ion beam and particle beam.
In a particle beam lithography process, a particle beam will pass through a resist layer and is internally scattered within the resist layer. An energy distribution from the particle beam, when applied to the resist layer, will affect the development of the resist layer, thereby affecting the critical dimensions of IC design. Therefore, how to accurately predict the energy distribution is a critical technology.